cs5535 National Semiconductor Corporation, cs5535 Datasheet - Page 73

• Manufacturer Part Number: cs5535
• Description: Geode Cs5535 Companion Multi-function South Bridge
• Manufacturer: National Semiconductor Corporation

Revision 0.8
Global Concepts and Features
• Power Management Controller (PMC) Standby
• PMC Standby registers starting at PMS I/O Offset 30h.
RTC domain
• Real Time Clock
3.9.2
ACPI power management is a standardized method to
manage power. An overview of the standard is presented
here. See Section 4.17 "Power Management Control" on
page 159 for a more complete discussion of ACPI support
in the CS5535. See ACPI specification v2.0 for complete
details on ACPI. A GX2/CS5535 system solution can fully
support all the requirements in the ACPI specification.
ACPI defines power states from a system perspective
down to a device perspective. There are four global system
states: G0 through G3. As a subset of the Global system
states G0-G2 there are six Sleep states: S0 through S5.
Within the sleep states S0-S1 there are five CPU states:
C0-C3 and CT, and three Device states: D0-D2. In a
GX2/CS5535 system design, the optional Sleep state S2,
and the CPU states C3 and CT (CPU Throttling) are not
supported. See Table 4-34 "Supported ACPI Power Man-
agement States" on page 159“. Table 4-34 shows how the
ACPI power states relate to each other. The table also
shows the condition of the power domains and the logic
within those domains with respect to the ACPI power
states.
Controller and associated I/O consisting of: WORKING,
WORK_AUX, and RESET_OUT.
See Table 5-68 "PM Support Registers Summary" on
page 478.
ACPI Power Management
(Continued)
73
3.9.3
Some systems rely solely on an APM (Advanced Power
Management) driver for enabling the operating system to
power-manage the CPU. APM provides several services
which enhance the system power management. It is a rea-
sonable approach to power management but APM has
some limitations:
• APM is an OS-specific driver, and may not be available
• Application support is inconsistent. Some applications in
• APM does not help with Suspend determination or
3.10 COMPONENT REVISION ID
The revision ID number of the CS5535 may be read in any
of the following places. All return the same value:
1)
2)
3)
The revision is an 8-bit value. Bits [7:4] indicate major revi-
sions while bits [3:0] indicate minor revisions. For example:
0x11
0x12
0x21
For listing of updates, refer to the document entitled Geode
CS5535 I/O Companion Device Errata.
for some operating systems.
foreground may prevent Idle calls.
peripheral power management.
GLCP_CHIP_REV_ID register: MSR 51700017h[7:0].
PCI Configuration Space Device Revision ID:
PCI Index 08h[15:0].
TAP Controller Revision register:
Instruction 8FFFFAh[7:0].
APM Power Management
A1
A2
B1
Value assigned to first manufactured
silicon of any new product.
Minor update to first silicon.
Major change to first silicon.
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